TY  - JOUR
AU  - Bachmann, B.
AU  - Offenhäusser, A.
AU  - Wolfrum, B.
AU  - Yakushenko, A.
AU  - Adly, Nouran
AU  - Krause, Kay
TI  - Three-dimensional inkjet-printed redox cycling sensor
JO  - RSC Advances
VL  - 7
IS  - 9
SN  - 2046-2069
CY  - London
PB  - RSC Publishing
M1  - FZJ-2017-01893
SP  - 5473 - 5479
PY  - 2017
AB  - Multilayer inkjet printing is emerging as a robust platform for fabricating flexible electronic devices over a large area. Here, we report a straightforward, scalable and inexpensive method for printing multilayer three-dimensional nanoporous redox cycling devices with a tunable nanometer gap for electrochemical sensing. The fabrication of the electrochemical redox cycling device is based on vertical stacking of two conductive electrodes made of carbon and gold nanoparticle inks. In this configuration, the two electrodes are parallel to each other and electrically separated by a layer of polystyrene nanospheres. As the top and the bottom electrodes are biased to, respectively, oxidizing and reducing potentials, repetitive cycling of redox molecules between them generates a large current amplification. We show that a vertical interelectrode spacing down to several hundred nanometers with high precision using inkjet printing is possible. The printed sensors demonstrate excellent performance in electrochemical sensing of ferrocene dimethanol as a redox-active probe. A collection efficiency of 100% and current amplification up to 30-fold could be obtained. Our method provides a low cost and versatile means for sensitive electrochemical measurements eliminating the need for sophisticated fabrication methods, which could prove useful for sensitive point-of-care diagnostics devices.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000393753200068
DO  - DOI:10.1039/C6RA27170G
UR  - https://juser.fz-juelich.de/record/827793
ER  -